Utilization of a gas chromatograph-mass spectrometer-computer system in pharmacological research is proposed in this grant application. The GC-MS-computer system will be used to characterize the organic acids appearing in the plasma and urine of primates which have been treated with toxic quantities of methanol and ethylene glycol. Other investigations involve the use of stable isotopes in conjunction with mass spectrometry. A sensitive and accurate dual collector mass spectrometer for the analysis of H2180 will be developed to measure body water in the newborn infant by isotope dilution. This method will be used to compare total body water in infants with pulmonary dysfunction after various treatments. GC-MS-computer procedures will be developed to quantitate extremely small amounts of neuropharmacologically significant molecules: tyrosine, dopamine, norepinephrine, and amphetamine. These compounds will be measured with the aid of stable isotope-labeled molecules serving as carrier and internal standard. Studies will be performed to investigate the correlation between behavior and the release of catecholamines from areas of the brain of animals treated with amphetamine. The development of a sensitive technique for the measurement of adenine nucleotides released following adrenergic nerve stimulation is being developed using high performance liquid chromatography.